Great fun with friends over local multiplayer, and the CPUs have been improved, but the online mode isn't very good. You are often quickly put into games that don't have the ruleset that you want, and there is no option to wait longer for a game with a ruleset close to yours. You will sometimes get thrown into 2 stock 3 minute games with items fighting an opponent who has terrible internet. Also the online uses a P2P system (this makes it laggy) which is really dumb considering you pay for Nintendo Switch Online.
Then again, the rest of the time you get put into matches with decently low lag and a good ruleset, and you have a good match, so I would still say its worth it to deal with the online.